A comparison of polychemotherapy and melphalan/prednisone for primary remission induction, and interferon-alpha for maintenance treatment, in multiple myeloma. A prospective trial of the German Myeloma Treatment Group.

406 untreated multiple myeloma patients of stage I (n = 54), II (n = 148) and III (n = 204) were enrolled in the trial. 51/54 stage I and 60/148 stage II patients were asymptomatic and followed without treatment until disease progression (progression free survival: 60% after 4 years for stage I versus 50% after 1 year for stage II). Symptomatic patients of stage I (n = 3/54) and II (n = 88/148) presenting with tumour progression, received melphalan 15 mg/m2 intravenously (i.v.) and prednisone 60 mg/m2 oral days 1-4 (MP). Stage II disease remission rate was 59%, and 50% tumour related survival (TRS) was 59 months. Stage III patients were randomised to receive MP or VBAMDex (vincristine/BCNU/doxorubicin/melphalan/dexamethasone) treatment. 43% of MP treated patients responded compared with 64% of the VBAMDex group. 50% TRS was 36 months in both groups without a detectable difference. 117 responders of stage II and III with stable disease were randomised to receive either IFN-alpha (5 x 10(6) IU, subcutaneous (S.C.) 3 times per week) or no maintenance treatment. The relapse rate in both groups was 50% after 13 months. No survival benefit for IFN alpha treated patients was observed (50% TRS: 45 months).